hash: add parse and build userdata interface

Add support for meta userdata area.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/src/expression.c b/src/expression.c
index 1791454ea466fd6a61a4550159c290b05e0f3e33..7cca342b2f1a4704973ce49aed3c32647e263781 100644 (file)
--- a/src/expression.c
+++ b/src/expression.c
@@ -1233,6 +1233,7 @@ const struct expr_ops *expr_ops_by_type(enum expr_types etype)
        case EXPR_OSF: return &osf_expr_ops;
        case EXPR_CT: return &ct_expr_ops;
        case EXPR_NUMGEN: return &numgen_expr_ops;
+       case EXPR_HASH: return &hash_expr_ops;
        default:
                break;
        }

diff --git a/src/hash.c b/src/hash.c
index 08e09099024ec9b75e427dfcd8762b83edc8d3c7..42c504073ae846c6d8910959930deb89ae7a3b67 100644 (file)
--- a/src/hash.c
+++ b/src/hash.c
@@ -61,6 +61,76 @@ static void hash_expr_destroy(struct expr *expr)
        expr_free(expr->hash.expr);
 }
 
+#define NFTNL_UDATA_HASH_TYPE 0
+#define NFTNL_UDATA_HASH_OFFSET 1
+#define NFTNL_UDATA_HASH_MOD 2
+#define NFTNL_UDATA_HASH_SEED 3
+#define NFTNL_UDATA_HASH_SEED_SET 4
+#define NFTNL_UDATA_HASH_MAX 5
+
+static int hash_expr_build_udata(struct nftnl_udata_buf *udbuf,
+                                const struct expr *expr)
+{
+       nftnl_udata_put_u32(udbuf, NFTNL_UDATA_HASH_TYPE, expr->hash.type);
+       nftnl_udata_put_u32(udbuf, NFTNL_UDATA_HASH_OFFSET, expr->hash.offset);
+       nftnl_udata_put_u32(udbuf, NFTNL_UDATA_HASH_MOD, expr->hash.mod);
+       nftnl_udata_put_u32(udbuf, NFTNL_UDATA_HASH_SEED, expr->hash.seed);
+       nftnl_udata_put_u32(udbuf, NFTNL_UDATA_HASH_SEED_SET, expr->hash.seed_set);
+
+       return 0;
+}
+
+static int hash_parse_udata(const struct nftnl_udata *attr, void *data)
+{
+       const struct nftnl_udata **ud = data;
+       uint8_t type = nftnl_udata_type(attr);
+       uint8_t len = nftnl_udata_len(attr);
+
+       switch (type) {
+       case NFTNL_UDATA_HASH_TYPE:
+       case NFTNL_UDATA_HASH_OFFSET:
+       case NFTNL_UDATA_HASH_SEED:
+       case NFTNL_UDATA_HASH_SEED_SET:
+       case NFTNL_UDATA_HASH_MOD:
+               if (len != sizeof(uint32_t))
+                       return -1;
+               break;
+       default:
+               return 0;
+       }
+
+       ud[type] = attr;
+       return 0;
+}
+
+static struct expr *hash_expr_parse_udata(const struct nftnl_udata *attr)
+{
+       const struct nftnl_udata *ud[NFTNL_UDATA_HASH_MAX + 1] = {};
+       uint32_t type, seed, seed_set, mod, offset;
+       int err;
+
+       err = nftnl_udata_parse(nftnl_udata_get(attr), nftnl_udata_len(attr),
+                               hash_parse_udata, ud);
+       if (err < 0)
+               return NULL;
+
+       if (!ud[NFTNL_UDATA_HASH_TYPE] ||
+           !ud[NFTNL_UDATA_HASH_OFFSET] ||
+           !ud[NFTNL_UDATA_HASH_SEED] ||
+           !ud[NFTNL_UDATA_HASH_MOD] ||
+           !ud[NFTNL_UDATA_HASH_SEED_SET])
+               return NULL;
+
+       type = nftnl_udata_get_u32(ud[NFTNL_UDATA_HASH_TYPE]);
+       offset = nftnl_udata_get_u32(ud[NFTNL_UDATA_HASH_OFFSET]);
+       seed = nftnl_udata_get_u32(ud[NFTNL_UDATA_HASH_SEED]);
+       seed_set = nftnl_udata_get_u32(ud[NFTNL_UDATA_HASH_SEED_SET]);
+       mod = nftnl_udata_get_u32(ud[NFTNL_UDATA_HASH_MOD]);
+
+       return hash_expr_alloc(&internal_location, mod, seed_set, seed,
+                              offset, type);
+}
+
 const struct expr_ops hash_expr_ops = {
        .type           = EXPR_HASH,
        .name           = "hash",
@@ -69,6 +139,8 @@ const struct expr_ops hash_expr_ops = {
        .cmp            = hash_expr_cmp,
        .clone          = hash_expr_clone,
        .destroy        = hash_expr_destroy,
+       .parse_udata    = hash_expr_parse_udata,
+       .build_udata    = hash_expr_build_udata,
 };
 
 struct expr *hash_expr_alloc(const struct location *loc,